Press focusing device for photographic diaphragms



Sept. 22, 1953 F. P. WILLCZOX 2,652,756

PRESS FOCUSING DEVICE FOR PHOTOGRAPHIC DIAPHRAGMS Original Filed Jan. 24, 1948 5 Sheets-Sheet l INVENTOR FREDERICK \lj/WIL CQX ATTORNEY p 1953 F. P. WILLCOX 2,652,756

PRESS FOCUSING DEVICE FOR PHOTOGRAPHIC DIAPHRAGMS Original Filed Jan. 24, 1948 3 SheetsSheet 2 INVENTOR FREDERICK P. WILLCOX ATTORNEY Sept. 22, 1953 F. P. WILLCOX PRESS FOCUSING DEVICE FOR PHOTOGRAPHI C DIAPHRAGMS 3 Sheets-Sheet 3 Original Filed Jan. 24, 1948 INVENTOR FREDERICK P, WIL OX Y Ly ATTORNEY Patented Sept. 22, 1953 PRESS FOCUSING DEVICE FOR PHOTO- GRAPHIC DIAPHRAGMS Frederick P. Willcox, Bethesda, Md., assignor to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware Original application January 24, 1948, Serial No. 4,114, now Patent No. 2,527,781, dated October 31, 1950. Divided and this application March 1, 1950, Serial No. 147,125

3 Claims.

This invention relates to a mechanism for socalled press focusing with photographic cameras such as those in which the image is viewed through the taking lens on a ground glass. This is a division of my co-pending application Serial No. 4,114, filed January 24, 1948, now Patent No. 2,527,781, issued October 31, 1950.

Among the objects of the invention is that of devising a press focusing mechanism which may be operated for opening both the shutter blades and the diaphragm by a single actuating means and, therefore, with one hand only.

Another object of the invention is that of devising a press focusing device which shall be effective by a single actuating means for opening both the shutter blades and the diaphragm, and for returning the shutter blades to closed position and thediaphragm to any preselected relative aperture by releasing that single actuating or control element.

Another object of the invention is that of devising a press focusing mechanism which shall be easily applied to shutters of the symmetrically opening type where the diaphragm and blades are located at or between the lens elements and which shall be relatively simple and dependable and effective in its operation.

Other objects of the invention will become apparent from the following more detailed description.

There have been a number of press focusing device described in prior patents and some have been employed commercially. However, most of these devices have been operated by two separate control members, one for the shutter blades and the other for the diaphragm or iris. Some shutters have means governing the return of the diaphragm to a predetermined position at which it may have been set prior to focusing on an object to be photographed.

Difliculties with the devices of the prior art arise from the fact that two separate manual operations are essential in that the shutter blades must be opened by a control therefor, and the diaphragm separately opened by the usual diaphragm setting means. After focusing, the photographer must take the necessary time and must remember to reset the diaphragm at whatever 2 toward two separate control elements at the shutter.

While there have been devices for limiting the return of the diaphragm to a particular stop, they have, insofar as applicant is aware, been a part only of the diaphragm mechanism and there has been no interconnection between the blade Opening means and the diaphragm so that the single control may serve for opening both elements, and upon release thereof, shall also serve to return both the shutter and diaphragm blades to the position intended. According to the invention, a diaphragm blade control ring is set by means of a diaphragm setting ring, lever, or other setting member, which functions through means such as a gear train and which, by its frictional contact with appropriate restraining members in the shutter, limits the movement of the diaphragm control mechanism in the direction of closing down the iris. By a pick-up mechanism forming a part of the gear train and which is adapted positively to open the diaphragm, the

focusing movement may be taken from a com- -bined blade opening and diaphragm opening control lever.

A spring-urged sector gear meshes with a part of the gear train to open the diaphragm for focusing purposes and functions when released, due to spring tension applied to it, to close the diaphragm to the point permitted by the preset diaphragm control member which dominates.

The pick-up mechanism always serves to stop and when the blades have reached a fully opened position. When the diaphragm is released by the pres focusing control member, the stop means which functions to retain the blade operating parts in an intermediate (blade open) position is withdrawn thereby to permit, the blades to c ose.

The invention will be described in detail by reference to one preferred embodiment thereof as from a portion of a trigger 2|.

3 applied to an interlens shutter and by reference to the accompanying figures of drawing, where- Fig. 1 is a front elevation of the assembled shutter, certain parts being broken away to show some of the diaphragm setting mechanism.

Fig. 2 is a view of the shutter with the front plates removed to show the press focusing mechanism and its relationship to the blade operating cam and release means therefor, the parts being shown in set position.

Fig. 2a is a view of the mechanism shown in Fig. 2, the parts being shown in the position they assume when the blades of both the shutter and the iris have been opened for focusing.

Fig. 3 is a detail view of the iris diaphragm itself.

Fig. 4 is a section through part of the shutter taken at line 4-4, Fig. 1.

Fig. 5 is an exploded View of the gear train, iris blade control ring and part of the iris-setting ring.

Now referring to Figs. 1 and 2, the invention has been illustrated in an interlens type shutter having symmetrically opening blades, this being a common type of shutter used with cameras in which so-called press focusing is practiced. The shutter includes, among other elements, a casing generally indicated by numeral I within which the usual len is centrally retained and between the elements of which are positioned the shutter blades II and an iris diaphragm having a plurality of blades 12, Fig. 3. The said shutter also has for operating the blades ll spring controlled mechanism comprising a cam l3 pivoted about a center I4 and which may be moved from an unset position to the set or cocked position of Fig. 2 by a setting lever l5.

The shutter operating cam I3 has a catch I which is engaged by a latch I! at one end of an arcuate release member I8 pivoted at I9 and engaged at its other end by a lug 20 struck up The trigger is in turn pivoted at 22 and is held in the position of Fig. 2 by a spring 23 in a conventional manner. For a more detailed description of the mechanism and operation of the basic shutter to which the present mechanism is applied, reference is made to application Serial No. 737,277, filed March 26, 1947, now Pat. No. 2,527,780,

issued October 31, 1950.

Referring to Fig. 3, the diaphragm blades [2 are pivoted at one end upon pins 24 and at their other ends, are controlled by a diaphragm blade ring 25 having slots within which project pins 27 fixed to the free end of the said blades. The

'pins 24 are, of course, fixed in a relatively immovable part within the shutter casing and the ring 25 is adapted to be rotated throughout a predetermined are by a gear 28 which meshes with teeth 29 cut at the surface of the ring. A pin 30 is fixed within the ring 25 and limits the movement thereof in either direction due to engagement with the ends of an arcuate slot 3|. This diaphragm mechanism itself is conventional although the operating means therefor is novel and is subject matter of co-pending apdesignated by numeral It carries at the front portion thereof a shutter speed setting ring 32 having suitable cams therein (not shown) for controlling the speed of the shutter and a second ring 33 by which the diaphragm is set at any desired opening or aperture. The ring 32 is frictionally held in set position while the ring 33 is likewise frictionally maintained in position, the two being separated by a thin washer 34 which has a projection or projections 35 extending into complementary keyways or serrations 35 in the central portion of the shutter casing thereby to prevent rotation of the washer. The inner surface of ring 33 is pressed against washer 34 by means of a spring or similar washer 31 held in position by the front plate 33 of the shutter.

The speed setting ring 32 and ring 33 have graduations at the faces thereof as shown in Fig. 1. These graduations on ring 33 permit the iris to be set at'relative openings in accordance with the designated numerals.

To operate the diaphragm, the ring 33 is r0- tated thereby rotating the diaphragm blade control ring 35 through a gear train shown in Figs. 4 and 5. The ring 33 has a toothed sector portion 39 which engages a pinion 40 at one end of a sleeve 4| mounted for rotation on a stud 42. Sleeve 4| has fixed at its other end a second pinion 43 which meshes with a gear 44 freely rotatable upon a reduced end 45 of a shaft 46 to which is fixed the gear 28 which meshes with the teeth 29 in the diaphragm blade control ring 25, Figs. 3, 4, and 5 Now referring to Figs. 2, 2a, and 5, the press focusing mechanism really comprises an extension to the diaphragm blade operating means which might otherwise have the gear 44 fixed to the shaft 46 so that, as disclosed in the application above mentioned, movements of the setting ring 33 would always bring about appropriate movements of the blades thereby to set them at any of the relative apertures within limits of which the device is designed to function. A press focusing lever or control member 41 is pivoted at 48and is normally urged in a counterclockwise direction about the pivot by a spring 49 coiled about the pivot 48 and engaging behind a small projection 50 at the inner end of the lever 41, a further function for which will be explained later.

A sector gear 5| is also pivoted about the same pivot screw 48 as the lever and has projecting therefrom a lug 52 engageable by the adjacent side of the lever 41. The sector gear is always urged in a counterclockwise direction (Fig. 2) about the pivot by means of spring 53. Gear 5| meshes with a small pinion 54 which is keyed to the end of the reduced portion of the shaft 46.

The pinion 54 has a pick-up" connection with the freely rotatable gear 44 on the extension 45 which comprises special disks 55 and 56. The disk 55 has a lug 51 which engages between gear teeth on the pinion 54 and a second lug 58 which engages an extension 59 on the second disk 56. The extension 59 in turn engages against the laterallydirected lug 60 extending from the side of the gear 44. The teeth on the pinion 54 are of greater length than those on the sector 5| to provide for engagement by the lug 51. The parts are properly assembled and timed so that the lug 5'! may project between the correct pair of teeth on the pinion at the same time.

When the parts are assembled with the pinion fixed at the end of the extension 45, the disks 55 various lugs and projections, the function of which will be explained hereinafter.

The setting ring 33 really serves as a means for positively opening the diaphragm blades and since it has a sufficient amount of frictional engagement with the adjacent parts at the shutter casing, it always limits the movement of the diaphragm members in a closing direction. It cannot positively move the blades to close them, that function being accomplished by the spring actuated sector gear 5| which, as before stated, always tends to close the blades although the setting ring 33 dominates so that the spring tensioned at the sector gear can only close th blades so far as the iris setting means will permit.

The movement of the lever 41 in a clockwise direction to the position of Fig. 20. causes the sector gear 5| to rotate the pinion 54 which, through the positively attached gear 28, turns the ring 25 until, at th extremity of movement for the parts, the diaphragm blades will be fully opened. Upon release of the said press focusing lever, the sector moves back under the influence of spring 53 thereby to close the blades to whatever relative opening has been previously set in accordance with the position of ring 33.

The gear 44 positively interconnected to the setting ring or segment 39 which forms a part thereof by the pinions 40, 43, and sleeve 4|, serves as a stop for this return movement. During the clockwise rotation of sector gear 5|, the disk 55 moves with the pinion and the lug 58 merely moves away from projection 59 and, in fact, after a complete revolution would again pick up that projection at its opposite side and may move it throughout almost a complete turn before it would again stop at the opposite side of the laterally projecting lug 60. This operation provides almost two free revolutions for the pinion 54 and gear 28 which is ample for movin the diaphragm blade control ring 25 throughout the angular extent necessary for control of the blades.

On the return movement of the parts, the sector gear 51 may rotate pinion 54 thereby closing the blades until the lug 58 engages projection 59 and that projection contacts laterally projecting lug 60 thereby stopping the parts at whatever preset iris opening has been chosen.

Now returning to Figs. 2 and 2a, the press focusing lever 41 has a first lug 6| which engages beneath one end 62 of a latch member 63 pivoted at 64. This latch member 63 has a laterally bent detent 65 which may engage the catch 16 on the cam [3 as illustrated in Fig. 21. A

spring 66 normally tends to hold the latch member in the position of Fig. 2 or its relatively inactive position. The end 62 of the lever is curved as illustrated so that after it has been swung to a position to stop the cam 13 after part of its travel, further movement of the lever 41 has no effect thereon.

The small extension on the press focus lever engages beneath a lug 61 at the hooked end of the release lever l8 and removes the latch 11 from the catch 16 thereby releasing the shutter operating cam to open the blades. The blade movement, however, progresses only so far as permitted by the latch member 63, i. e., far enough to open the blades completely.

The timing of the parts is such that as the lever 41 is swung from relatively inactive position to its complete limit of travel, Fig. 2a, the lug 6| first engages beneath the end 62 of the latching lever to raise it and move the other end down to a position in which the lug 65 stands in the pathway of the catch l6. Then the projection 50 withdraws the latch 6-0 thereby permitting its cam to make its upward movement. Depending upon the setting of the diaphragm the lever 41 picks up lug 52 on the sector gear at some point in its travel and through the mechanism above described and illustrated in Fig. 5, opens the diaphragm blades to their fullest extent.

Return or release of the lever 41 permits the spring 53 to return the sector gear as far as it will go thereby to return the diaphragm blades to whatever stop the diaphragm setting ring has been preset. Then, upon engagement of a second lug 68 on the lever 41 upon the top of the end 62 of lever 63, the lever is so swung away from the position of Fig. 2a that the cam I3 is released and permitted to return to its initial or unset position. This closes the shutter blades. The spring 66 may normally be relied upon to hold th latching lever 63 in its inactive position, but lug 68 by contact with the lever positively withdraws the detent 65 so that the function is not dependent upon a spring. After releasing the press focus lever 41, the shutter may again be set and the picture taken.

Operation To sum up the operation of the device, it may be assumed that it is desired to focus upon some particular object and that the shutter is not in cocked position. The shutter is first set so that the cam 13 takes the position shown in Fig. 2. Then the press focus lever 41 is pushed over toward the right to the position of Fig. 2a, whereupon the sector gear 5| is picked up by the lever sooner or later, depending upon the setting of the diaphragm which, let us assume, is set at f-8. At that setting the lever 41 may be moved about halfway of its complete travel before it picks up the sector gear.

Rotation of the sector gear as the lever is moved to the end of its travel causes the dia- ,trol ring 25 to the end of its travel in a direction for opening the blades.

During the swinging of lever 41 from one extreme position to the other, lug 6| thereon engages beneath the end 62 of the latching lever and moves the detent 65 to a position in which it will engage catch 16 on the cam l3 after the cam has been released. The timing is such that detent 65 is moved to a position slightly in advance of contact between the projection 50 and lug 61 on the release lever l8. The last few degrees of movement of the press focusing lever causes latch l1 to withdraw from the catch l6 thereby permitting the cam 13 to move to the position of Fig- 2a Where it is stopped by the latching lever and in which position it will have moved the shutter blades until they are fully opened.

The press focusing lever 41 is held in the position of Fig. 20, as long as it is desired to view the image on the ground glass and, when focusing has draw the slide as is the usual practice. jvice is virtually fool-proof since only one control 1 blades.

:been set.

pinion 6'4 and gear!!! to close down the iris until the lug 58 becomes engaged With extension 59 which will, in turn, bear against the projection 60 on the gear 44. Contact of these parts stops the closing movement of the diaphragm blades and this occurs at whatever point the ring 33 has been set, e. g., at f-8 as above assumed.

To take the picture, it is then necessary to recock the shutter, insert the film holder and with- The demeans, lever 41, is employed. One cannot see the image to focus unless the shutter has first been cooked and unless the lever 41 is pushed downwardly nearly to its fullest extent thereby to open not only the diaphragm, but also the shutter Upon release of the lever, it must return to its initial position and this return movement is almost immediately accompanied by release of the shutter blades which move to their closed position and an automatic closing down of the diaphragm to whatever stop it had previously There is no possibility of taking the photograph with the diaphragm shaft completely open unless the setting has been intended and the ring 33 accordingly positioned.

Focusing is normally taken care of by turning a focusing knob or moving some similar control "with the right hand while the press focus lever 41 is held down with the left hand. After the image has been brought into focus and the picture properly composed on the ground glass, the

release of the press focusing lever is all that is necessary to return the parts to proper position after which the photographer may take the picture by placing the film or plate as is the usual practice and thereupon cocking the shutter and releasing it in the usual manner.

If the camera to which this mechanism is applied is one of the type known as a single lens reflex, the film may be positioned in readiness for having the latent image impressed thereon, and

'it is only necessary after focusing, to release the press focus lever, set the shutter, and then to release it in the usual manner for taking the photograph.

While the invention has been described as applied to a particular interlens shutter, it is to be understood that the description is illustrative of one embodiment the invention may take and that the principles of the invention may be applied to virtually all interlens shutters or similar shutters having diaphragms and that the shutter operating mechanism may comprise elements other than or different from the cam l3, for, example,

an oscillatory disk or other member desired to impart movement through a connecting link or the like. In this event, the latching member is merely modified so as to restrain the parts in the position necessary to hold the shutter blades in 'the blades in open position without keeping the hand on the press focus lever. If so, there may be enough frictional contact between the lug GI and the curved end of the lever arm 62 so that the lever 41 will return only if moved counterclockwise positively.

Alternatively, a latch means may be provided outside the shutter casing and may be used only when it is desired to dispense with the feature of automatic return upon release of the lever 41. These permit the blades to be held open while both hands are kept free for manipulating other parts.

While one embodiment of the invention has been disclosed, it is to be understood that the inventive concept may be carried out in a number of ways. This application is, therefore, not to be limited to the precise details described, but is intended to cover al1 variations and modifications thereof falling Within the spirit of the invention and the scope of the claims.

I claim:

1. A diaphragm opening arrangement for photographic cameras comprising a housing, a diaphragm blade ring having peripheral gear teeth and a diaphragm setting ring having peripheral gear teeth, said rings being coaxially placed within said housing at a predetermined distance, a mechanical intercoupling between said rings including an actuating gear for said first-mentioned ring having a shaft, an idler gear on said shaft, gearing means interconnecting said idler gear and said diaphragm setting ring, a pinion keyed to said shaft, unidirectional coupling means on said shaft driven by said idler gear, means for coupling said pinion and said unidirectional coupling means, a sector gear meshing with said pinion, spring means urging said sector gear in one direction, a manually operable focusing lever for positioning said sector gear, and thereby opening said diaphragm the relative position of said unidirectional coupling means determining the extent of movement of said sector gear upon release of said lever in closing said diaphragm.

2. A diaphragm opening arrangement for photographic cameras comprising a housing, a diaphragm blade ring having peripheral gear teeth and a diaphragm setting ring having peripheral gear teeth, said rings being coaxially placed within said housing at a predetermined ion keyed to said shaft means for coupling said pinion and said unidirectional coupling means, a sector gear meshing with said pinion, spring means urging said sector gear in one direction, a manually operable focusing lever for positioning said sector gear and thereby opening said diaphragm, the relative position of said discs in said shaft determining the extent of movement of said sector gear upon release of said lever for closing said diaphragm.

3. A diaphragm opening arrangement for photographic cameras comprising a housing, a diaphragm blade ring having peripheral gear teeth and a diaphragm setting ring having peripheral gear teeth, said rings being coaxially placed within said housing at a predetermined distance, a mechanical intercoupling between said rings including an actuating gear for said first-mentioned ring having a'shaft, an idler gear on said shaft, gearing means interconnecting said idler gear and said diaphragm setting ring, unidirectional coupling means comprising concentric discs having engaging extensions on said shaft driven by an extension on said idler gear, a

pinion keyed to said shaft, an extension on one of 5 said discs engaging a gear tooth on said pinion for coupling said pinion and said unidirectional coupling means, a sector gear meshing with said pinion, spring means urging said sector gear in one direction, a manually operable focusing lever for positioning said sector gear and thereby opening said diaphragm, the relative position of said discs on said shaft determining the extent of movement of said sector gear upon release of said lever and closing said diaphragm.

FREDERICK P. WILLCOX.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,262,509 McNabb Nov. 11, 1941 2,341,387 Riddell Feb. 8, 1944 2,527,781 Wiilcox Oct. 31, 1950 

